feat: art images and queue

app/src/main/kotlin/ca/ksamad/musicremote/MusicRemoteApplication.kt

@@ -1,13 +1,21 @@
 package ca.ksamad.musicremote
 
 import android.app.Application
+import ca.ksamad.musicremote.playback.ArtImageLoader
 import ca.ksamad.musicremote.playback.MpdConnectionManager
+import coil3.ImageLoader
+import coil3.PlatformContext
+import coil3.SingletonImageLoader
 
 /**
  * Holds the app-scoped [MpdConnectionManager] so the MPD connection outlives any
- * single Activity and can be shared with the foreground [ca.ksamad.musicremote.playback.PlaybackService].
+ * single Activity and can be shared with the foreground
+ * [ca.ksamad.musicremote.playback.PlaybackService].
+ *
+ * Also the Coil [SingletonImageLoader.Factory], wiring cover-art loading to that
+ * same manager so `AsyncImage` calls anywhere in the app fetch (and cache) MPD art.
  */
-class MusicRemoteApplication : Application() {
+class MusicRemoteApplication : Application(), SingletonImageLoader.Factory {
 
     val manager: MpdConnectionManager by lazy { MpdConnectionManager(this) }
 
@@ -17,4 +25,7 @@ class MusicRemoteApplication : Application() {
         // as soon as the process starts, not only when the UI first observes it.
         manager
     }
+
+    override fun newImageLoader(context: PlatformContext): ImageLoader =
+        ArtImageLoader.create(context, manager)
 }

app/src/main/kotlin/ca/ksamad/musicremote/mpd/MpdClient.kt

@@ -17,7 +17,9 @@ import kotlinx.coroutines.flow.asStateFlow
 import kotlinx.coroutines.isActive
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.Semaphore
 import kotlinx.coroutines.sync.withLock
+import kotlinx.coroutines.sync.withPermit
 import kotlinx.coroutines.withContext
 import java.io.IOException
 
@@ -112,6 +114,9 @@ class MpdClient(
                 command.execute(MpdCommands.password(pw))
                 idle.execute(MpdCommands.password(pw))
             }
+            // Bigger binary chunks → album art transfers in ~1 round-trip.
+            // Best-effort: ignore if the server rejects it (old MPD).
+            runCatching { command.execute(MpdCommands.binaryLimit(BINARY_LIMIT)) }
             commandConn = command
             idleConn = idle
         }
@@ -126,6 +131,7 @@ class MpdClient(
             idleConn?.close()
             commandConn?.close()
         }
+        closeArtConnections()
         idleConn = null
         commandConn = null
         if (_connectionState.value !is MpdConnectionState.Error) {
@@ -189,6 +195,43 @@ class MpdClient(
         conn.execute(MpdCommands.play())
     }
 
+    /** Cover art bytes for a specific song URI, or null if the server has none. */
+    suspend fun songArt(uri: String): ByteArray? = withArtConnection { conn -> readArt(conn, uri) }
+
+    /** Cover art bytes for an album (resolves a representative track first). */
+    suspend fun albumArt(album: String, albumArtist: String?): ByteArray? = withArtConnection { conn ->
+        val trackUri = conn.execute(MpdCommands.findFirstTrack(album, albumArtist))
+            .split().firstOrNull()?.get("file")
+            ?: return@withArtConnection null
+        readArt(conn, trackUri)
+    }
+
+    /** Try folder cover (`albumart`), then embedded art (`readpicture`). */
+    private fun readArt(conn: MpdConnection, uri: String): ByteArray? =
+        readArtChunks(conn, embedded = false, uri) ?: readArtChunks(conn, embedded = true, uri)
+
+    /** Loop the chunked art protocol until the whole image (per `size:`) is read. */
+    private fun readArtChunks(conn: MpdConnection, embedded: Boolean, uri: String): ByteArray? {
+        val out = java.io.ByteArrayOutputStream()
+        var offset = 0
+        while (true) {
+            val resp = try {
+                conn.execute(
+                    if (embedded) MpdCommands.readPicture(uri, offset) else MpdCommands.albumArt(uri, offset),
+                )
+            } catch (e: MpdAckException) {
+                return null // no such art
+            }
+            val chunk = resp.binary
+            if (chunk == null || chunk.isEmpty()) break
+            out.write(chunk)
+            offset += chunk.size
+            val size = resp["size"]?.toIntOrNull() ?: break
+            if (offset >= size) break
+        }
+        return if (out.size() > 0) out.toByteArray() else null
+    }
+
     // --- Internals ----------------------------------------------------------
 
     private suspend fun run(commandLine: String) {
@@ -214,6 +257,67 @@ class MpdClient(
             }
         }
 
+    // --- Art connection pool -----------------------------------------------
+    //
+    // Cover fetches run on their own small pool of connections rather than the
+    // command connection, so (a) many covers load in parallel while scrolling and
+    // (b) art never blocks play/pause/volume. Connections are opened lazily, up
+    // to ART_POOL_SIZE (bounded by the semaphore), reused when idle, and dropped
+    // on any transport error (a stale/timed-out one just gets reopened).
+
+    private val artSemaphore = Semaphore(ART_POOL_SIZE)
+    private val artPoolLock = Any()
+    private val idleArtConnections = ArrayDeque<MpdConnection>()
+
+    private suspend fun <T> withArtConnection(block: (MpdConnection) -> T): T =
+        artSemaphore.withPermit {
+            val conn = borrowArtConnection()
+            try {
+                val result = withContext(ioDispatcher) { block(conn) }
+                returnArtConnection(conn)
+                result
+            } catch (e: MpdAckException) {
+                returnArtConnection(conn) // command refused, but connection is healthy
+                throw e
+            } catch (e: Throwable) {
+                runCatching { conn.close() } // discard a broken connection
+                throw e
+            }
+        }
+
+    private suspend fun borrowArtConnection(): MpdConnection {
+        synchronized(artPoolLock) { idleArtConnections.removeFirstOrNull() }?.let { return it }
+        return withContext(ioDispatcher) {
+            val h = host ?: throw MpdConnectionException("not connected")
+            val conn = connectionFactory(h, port, COMMAND_READ_TIMEOUT_MS)
+            password?.let { conn.execute(MpdCommands.password(it)) }
+            runCatching { conn.execute(MpdCommands.binaryLimit(BINARY_LIMIT)) }
+            conn
+        }
+    }
+
+    private fun returnArtConnection(conn: MpdConnection) {
+        val kept = synchronized(artPoolLock) {
+            if (idleArtConnections.size < ART_POOL_SIZE) {
+                idleArtConnections.addLast(conn)
+                true
+            } else {
+                false
+            }
+        }
+        if (!kept) runCatching { conn.close() }
+    }
+
+    /** Close and drop all pooled art connections (on disconnect/reconnect/teardown). */
+    private fun closeArtConnections() {
+        val toClose = synchronized(artPoolLock) {
+            val copy = idleArtConnections.toList()
+            idleArtConnections.clear()
+            copy
+        }
+        toClose.forEach { runCatching { it.close() } }
+    }
+
     /** Re-read `status` and `currentsong` into the flows (single round-trip). */
     private suspend fun refresh() {
         val (status, song) = withCommand { conn ->
@@ -311,6 +415,7 @@ class MpdClient(
         }
         idleConn = null
         commandConn = null
+        closeArtConnections()
     }
 
     private fun failAndClose(message: String) {
@@ -320,6 +425,8 @@ class MpdClient(
 
     companion object {
         private const val COMMAND_READ_TIMEOUT_MS = 10_000
+        private const val BINARY_LIMIT = 512 * 1024
+        private const val ART_POOL_SIZE = 4
         private const val KEEPALIVE_INTERVAL_MS = 25_000L
         private const val RECONNECT_BACKOFF_MS = 1_000L
         private const val MAX_RECONNECT_ATTEMPTS = 5

app/src/main/kotlin/ca/ksamad/musicremote/mpd/MpdCommands.kt

@@ -79,4 +79,23 @@ object MpdCommands {
         } else {
             MpdProtocol.command("findadd", "album", album, "albumartist", albumArtist)
         }
+
+    /** First track of an album — used to resolve a URI for album-art lookup. */
+    fun findFirstTrack(album: String, albumArtist: String?) =
+        if (albumArtist.isNullOrEmpty()) {
+            MpdProtocol.command("find", "album", album, "window", "0:1")
+        } else {
+            MpdProtocol.command("find", "album", album, "albumartist", albumArtist, "window", "0:1")
+        }
+
+    // --- Album art ----------------------------------------------------------
+
+    /** Folder cover art for [uri]'s directory, starting at [offset] (chunked binary). */
+    fun albumArt(uri: String, offset: Int) = MpdProtocol.command("albumart", uri, offset.toString())
+
+    /** Embedded picture from the file at [uri], starting at [offset] (chunked binary). */
+    fun readPicture(uri: String, offset: Int) = MpdProtocol.command("readpicture", uri, offset.toString())
+
+    /** Raise the per-response binary chunk size so art transfers in fewer round-trips. */
+    fun binaryLimit(bytes: Int) = MpdProtocol.command("binarylimit", bytes.toString())
 }

app/src/main/kotlin/ca/ksamad/musicremote/mpd/MpdException.kt

@@ -52,7 +52,10 @@ class MpdAckException(
 
     companion object {
         // ACK [2@1] {play} Bad song index
-        private val PATTERN = Regex("""ACK \[(\d+)@(\d+)] \{([^}]*)} ?(.*)""")
+        // NB: `]` and `}` are escaped. The JVM regex engine tolerates them bare,
+        // but Android's ICU engine rejects an unescaped `]`/`}`, which would make
+        // this Regex fail to compile at class-init time (only on-device).
+        private val PATTERN = Regex("""ACK \[(\d+)@(\d+)\] \{([^}]*)\} ?(.*)""")
 
         /**
          * Parse a raw `ACK …` response line. Returns `null` if [line] is not a

app/src/main/kotlin/ca/ksamad/musicremote/playback/ArtImageLoader.kt

@@ -0,0 +1,117 @@
+package ca.ksamad.musicremote.playback
+
+import coil3.ImageLoader
+import coil3.PlatformContext
+import coil3.decode.DataSource
+import coil3.decode.ImageSource
+import coil3.disk.DiskCache
+import coil3.fetch.FetchResult
+import coil3.fetch.Fetcher
+import coil3.fetch.SourceFetchResult
+import coil3.key.Keyer
+import coil3.request.Options
+import okio.Buffer
+import okio.FileSystem
+import okio.Path.Companion.toOkioPath
+
+/**
+ * Builds the Coil [ImageLoader] that serves MPD cover art. Art bytes come from
+ * [MpdConnectionManager.fetchArt] via a custom [Fetcher].
+ *
+ * Coil's disk cache is only auto-managed by its network fetchers, so a custom
+ * fetcher must read/write the [DiskCache] itself — otherwise art is only
+ * memory-cached and every cold start re-fetches from the server. [MpdArtFetcher]
+ * therefore checks the disk cache first, and write-through-caches misses, so each
+ * cover is fetched from the (tiny) server exactly once, ever.
+ */
+object ArtImageLoader {
+
+    fun create(context: PlatformContext, manager: MpdConnectionManager): ImageLoader =
+        ImageLoader.Builder(context)
+            .components {
+                add(MpdArtKeyer(), MpdArtData::class)
+                add(MpdArtFetcher.Factory { manager.fetchArt(it) }, MpdArtData::class)
+            }
+            .diskCache {
+                DiskCache.Builder()
+                    .directory(context.cacheDir.resolve("mpd_art").toOkioPath())
+                    .maxSizeBytes(64L * 1024 * 1024)
+                    .build()
+            }
+            .build()
+
+    /** Stable cache key per art request; shared by the keyer and the disk cache. */
+    private fun cacheKey(data: MpdArtData): String = when (data) {
+        is SongArt -> "song:${data.uri}"
+        is AlbumArt -> "album:${data.albumArtist.orEmpty()}/${data.album}"
+    }
+
+    private class MpdArtKeyer : Keyer<MpdArtData> {
+        override fun key(data: MpdArtData, options: Options): String = cacheKey(data)
+    }
+
+    private class MpdArtFetcher(
+        private val data: MpdArtData,
+        private val diskCache: DiskCache?,
+        private val fetch: suspend (MpdArtData) -> ByteArray?,
+    ) : Fetcher {
+
+        override suspend fun fetch(): FetchResult? {
+            val key = cacheKey(data)
+
+            // 1. Serve from disk cache if present (survives process death).
+            diskCache?.openSnapshot(key)?.let { snapshot ->
+                return sourceResult(snapshot, key, DataSource.DISK)
+            }
+
+            // 2. Miss → fetch from the server.
+            val bytes = fetch(data) ?: return null
+
+            // 3. Write-through to the disk cache, then serve from it.
+            writeToDiskCache(key, bytes)?.let { snapshot ->
+                return sourceResult(snapshot, key, DataSource.NETWORK)
+            }
+
+            // 4. Fallback (no disk cache / write failed): serve from memory.
+            return SourceFetchResult(
+                source = ImageSource(Buffer().apply { write(bytes) }, FileSystem.SYSTEM),
+                mimeType = null,
+                dataSource = DataSource.NETWORK,
+            )
+        }
+
+        private fun writeToDiskCache(key: String, bytes: ByteArray): DiskCache.Snapshot? {
+            val cache = diskCache ?: return null
+            val editor = cache.openEditor(key) ?: return null
+            return try {
+                cache.fileSystem.write(editor.data) { write(bytes) }
+                editor.commitAndOpenSnapshot()
+            } catch (e: Exception) {
+                editor.abort()
+                null
+            }
+        }
+
+        private fun sourceResult(
+            snapshot: DiskCache.Snapshot,
+            key: String,
+            dataSource: DataSource,
+        ): SourceFetchResult = SourceFetchResult(
+            source = ImageSource(
+                file = snapshot.data,
+                fileSystem = diskCache!!.fileSystem,
+                diskCacheKey = key,
+                closeable = snapshot,
+            ),
+            mimeType = null,
+            dataSource = dataSource,
+        )
+
+        class Factory(
+            private val fetch: suspend (MpdArtData) -> ByteArray?,
+        ) : Fetcher.Factory<MpdArtData> {
+            override fun create(data: MpdArtData, options: Options, imageLoader: ImageLoader): Fetcher =
+                MpdArtFetcher(data, imageLoader.diskCache, fetch)
+        }
+    }
+}

app/src/main/kotlin/ca/ksamad/musicremote/playback/MpdArt.kt

@@ -0,0 +1,14 @@
+package ca.ksamad.musicremote.playback
+
+/**
+ * A request for a piece of MPD cover art, used as the model handed to Coil. The
+ * concrete type doubles as the cache key (see the keyer in [ArtImageLoader]), so
+ * the same song/album resolves to the same cached image.
+ */
+sealed interface MpdArtData
+
+/** Cover art for a specific song URI (used for now-playing and the notification). */
+data class SongArt(val uri: String) : MpdArtData
+
+/** Cover art for an album (a representative track is resolved server-side). */
+data class AlbumArt(val album: String, val albumArtist: String?) : MpdArtData

app/src/main/kotlin/ca/ksamad/musicremote/playback/MpdConnectionManager.kt

@@ -6,6 +6,7 @@ import ca.ksamad.musicremote.data.SettingsRepository
 import ca.ksamad.musicremote.mpd.MpdClient
 import ca.ksamad.musicremote.mpd.MpdConnectionState
 import ca.ksamad.musicremote.mpd.model.MpdAlbum
+import ca.ksamad.musicremote.mpd.model.MpdSong
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.SupervisorJob
@@ -130,12 +131,27 @@ class MpdConnectionManager(context: Context) {
     }
     fun setRepeat(on: Boolean) = fire { setRepeat(on) }
     fun setRandom(on: Boolean) = fire { setRandom(on) }
+    fun setConsume(on: Boolean) = fire { setConsume(on) }
 
     fun playAlbum(album: String, albumArtist: String?) = fire { playAlbum(album, albumArtist) }
 
+    /** Jump to a queue entry by its stable song id. */
+    fun playQueueItem(songId: Int) = fire { playId(songId) }
+
     /** One-shot library fetch; returns empty on any failure. */
     suspend fun loadAlbums(): List<MpdAlbum> = runCatching { client.albums() }.getOrDefault(emptyList())
 
+    /** One-shot play-queue fetch; returns empty on any failure. */
+    suspend fun loadQueue(): List<MpdSong> = runCatching { client.queue() }.getOrDefault(emptyList())
+
+    /** Fetch cover-art bytes for Coil (null on miss/failure). */
+    suspend fun fetchArt(data: MpdArtData): ByteArray? = runCatching {
+        when (data) {
+            is SongArt -> client.songArt(data.uri)
+            is AlbumArt -> client.albumArt(data.album, data.albumArtist)
+        }
+    }.getOrNull()
+
     /**
      * True when we own the volume: connected to a server that exposes a mixer.
      * Used to decide whether hardware volume keys drive the *server* (silently,

app/src/main/kotlin/ca/ksamad/musicremote/playback/PlaybackService.kt

@@ -6,6 +6,7 @@ import android.app.PendingIntent
 import android.app.Service
 import android.content.Context
 import android.content.Intent
+import android.graphics.Bitmap
 import android.os.Build
 import android.os.IBinder
 import android.support.v4.media.MediaMetadataCompat
@@ -17,6 +18,10 @@ import androidx.core.content.ContextCompat
 import androidx.media.VolumeProviderCompat
 import androidx.media.app.NotificationCompat.MediaStyle
 import androidx.media.session.MediaButtonReceiver
+import coil3.SingletonImageLoader
+import coil3.request.ImageRequest
+import coil3.request.SuccessResult
+import coil3.toBitmap
 import ca.ksamad.musicremote.MainActivity
 import ca.ksamad.musicremote.MusicRemoteApplication
 import ca.ksamad.musicremote.R
@@ -28,7 +33,10 @@ import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.SupervisorJob
 import kotlinx.coroutines.cancel
+import kotlinx.coroutines.flow.collectLatest
 import kotlinx.coroutines.flow.combine
+import kotlinx.coroutines.flow.distinctUntilChanged
+import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.launch
 
 /**
@@ -103,6 +111,10 @@ class PlaybackService : Service() {
         override fun onSeekTo(pos: Long) = manager.seekTo(pos / 1000.0)
     }
 
+    // Album art for the session/notification, cached against the song it's for.
+    private var artUri: String? = null
+    private var artBitmap: Bitmap? = null
+
     private fun observeState() {
         scope.launch {
             combine(manager.status, manager.currentSong) { s, song -> s to song }
@@ -113,6 +125,21 @@ class PlaybackService : Service() {
                     postNotification()
                 }
         }
+        // Fetch cover art on song change (via Coil, so it shares the app's cache)
+        // and re-publish the metadata/notification once it arrives.
+        scope.launch {
+            manager.currentSong
+                .map { it?.uri }
+                .distinctUntilChanged()
+                .collectLatest { uri ->
+                    artUri = uri
+                    artBitmap = if (uri != null) loadArtBitmap(uri) else null
+                    if (artUri == uri) {
+                        session.setMetadata(buildMetadata(manager.currentSong.value, manager.status.value))
+                        postNotification()
+                    }
+                }
+        }
         scope.launch {
             manager.connectionState.collect { st ->
                 if (st is MpdConnectionState.Disconnected || st is MpdConnectionState.Error) {
@@ -123,6 +150,13 @@ class PlaybackService : Service() {
         }
     }
 
+    private suspend fun loadArtBitmap(uri: String): Bitmap? {
+        val result = SingletonImageLoader.get(applicationContext).execute(
+            ImageRequest.Builder(applicationContext).data(SongArt(uri)).build(),
+        )
+        return (result as? SuccessResult)?.image?.toBitmap()
+    }
+
     private fun buildMetadata(song: MpdSong?, status: MpdStatus?): MediaMetadataCompat =
         MediaMetadataCompat.Builder().apply {
             putString(MediaMetadataCompat.METADATA_KEY_TITLE, song?.title ?: song?.uri ?: "")
@@ -130,6 +164,9 @@ class PlaybackService : Service() {
             putString(MediaMetadataCompat.METADATA_KEY_ALBUM, song?.album ?: "")
             val durationMs = ((song?.duration ?: status?.duration ?: 0.0) * 1000).toLong()
             putLong(MediaMetadataCompat.METADATA_KEY_DURATION, durationMs)
+            if (artBitmap != null && artUri == song?.uri) {
+                putBitmap(MediaMetadataCompat.METADATA_KEY_ALBUM_ART, artBitmap)
+            }
         }.build()
 
     private fun buildPlaybackState(status: MpdStatus?): PlaybackStateCompat {

app/src/main/kotlin/ca/ksamad/musicremote/ui/AlbumsScreen.kt

@@ -4,11 +4,12 @@ import androidx.compose.foundation.clickable
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.automirrored.filled.ArrowBack
-import androidx.compose.material.icons.filled.Album
 import androidx.compose.material3.CircularProgressIndicator
 import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.Icon
@@ -23,9 +24,11 @@ import androidx.compose.runtime.getValue
 import androidx.compose.runtime.produceState
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
 import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.unit.dp
 import ca.ksamad.musicremote.mpd.model.MpdAlbum
+import ca.ksamad.musicremote.playback.AlbumArt
 
 /**
  * Browse every album on the server. Tapping one replaces the queue with that
@@ -75,7 +78,13 @@ fun AlbumsScreen(vm: PlayerViewModel, onBack: () -> Unit, onPlay: () -> Unit) {
                             onPlay()
                         },
                         leadingContent = {
-                            Icon(Icons.Filled.Album, contentDescription = null)
+                            ArtImage(
+                                model = AlbumArt(album.name, album.albumArtist),
+                                iconSize = 24.dp,
+                                modifier = Modifier
+                                    .size(48.dp)
+                                    .clip(RoundedCornerShape(6.dp)),
+                            )
                         },
                         headlineContent = {
                             Text(album.name, maxLines = 1, overflow = TextOverflow.Ellipsis)

app/src/main/kotlin/ca/ksamad/musicremote/ui/ArtImage.kt

@@ -0,0 +1,45 @@
+package ca.ksamad.musicremote.ui
+
+import androidx.compose.foundation.background
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.size
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.Album
+import androidx.compose.material3.Icon
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.layout.ContentScale
+import androidx.compose.ui.unit.Dp
+import coil3.compose.AsyncImage
+
+/**
+ * Cover art with a disc-icon placeholder. Draws the placeholder underneath and
+ * lets the [AsyncImage] paint over it once (and if) art loads — so a missing
+ * cover, a still-loading fetch, and a solid image all look right. [model] is an
+ * [ca.ksamad.musicremote.playback.MpdArtData] (or null to show just the placeholder).
+ */
+@Composable
+fun ArtImage(model: Any?, iconSize: Dp, modifier: Modifier = Modifier) {
+    Box(
+        modifier = modifier.background(MaterialTheme.colorScheme.surfaceVariant),
+        contentAlignment = Alignment.Center,
+    ) {
+        Icon(
+            Icons.Filled.Album,
+            contentDescription = null,
+            modifier = Modifier.size(iconSize),
+            tint = MaterialTheme.colorScheme.onSurfaceVariant,
+        )
+        if (model != null) {
+            AsyncImage(
+                model = model,
+                contentDescription = null,
+                modifier = Modifier.fillMaxSize(),
+                contentScale = ContentScale.Crop,
+            )
+        }
+    }
+}

app/src/main/kotlin/ca/ksamad/musicremote/ui/MusicRemoteApp.kt

@@ -32,7 +32,7 @@ import ca.ksamad.musicremote.data.ConnectionSettings
  * (first run, after disconnect, or on error), or the now-playing screen.
  */
 /** Sub-screens layered over the player (no nav library needed for this few). */
-private enum class PlayerOverlay { None, Settings, Albums }
+private enum class PlayerOverlay { None, Settings, Albums, Queue }
 
 @Composable
 fun MusicRemoteApp(vm: PlayerViewModel = viewModel()) {
@@ -55,10 +55,12 @@ fun MusicRemoteApp(vm: PlayerViewModel = viewModel()) {
                 onBack = { overlay = PlayerOverlay.None },
                 onPlay = { overlay = PlayerOverlay.None },
             )
+            PlayerOverlay.Queue -> QueueScreen(vm, onBack = { overlay = PlayerOverlay.None })
             PlayerOverlay.None -> NowPlayingScreen(
                 vm,
                 onOpenSettings = { overlay = PlayerOverlay.Settings },
                 onOpenLibrary = { overlay = PlayerOverlay.Albums },
+                onOpenQueue = { overlay = PlayerOverlay.Queue },
             )
         }
     }

app/src/main/kotlin/ca/ksamad/musicremote/ui/NowPlayingScreen.kt

@@ -1,5 +1,7 @@
 package ca.ksamad.musicremote.ui
 
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.verticalScroll
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.Row
@@ -9,7 +11,9 @@ import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.QueueMusic
 import androidx.compose.material.icons.filled.Cast
 import androidx.compose.material.icons.filled.LibraryMusic
 import androidx.compose.material.icons.filled.Pause
@@ -37,11 +41,13 @@ import androidx.compose.runtime.remember
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
 import androidx.compose.ui.text.style.TextAlign
 import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.unit.dp
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import ca.ksamad.musicremote.mpd.model.MpdStatus
+import ca.ksamad.musicremote.playback.SongArt
 import ca.ksamad.musicremote.mpd.model.PlayerState
 import kotlinx.coroutines.delay
 
@@ -56,6 +62,7 @@ fun NowPlayingScreen(
     vm: PlayerViewModel,
     onOpenSettings: () -> Unit,
     onOpenLibrary: () -> Unit,
+    onOpenQueue: () -> Unit,
 ) {
     val status by vm.status.collectAsStateWithLifecycle()
     val song by vm.currentSong.collectAsStateWithLifecycle()
@@ -64,11 +71,15 @@ fun NowPlayingScreen(
     Column(
         modifier = Modifier
             .fillMaxSize()
+            .verticalScroll(rememberScrollState())
             .padding(24.dp),
         horizontalAlignment = Alignment.CenterHorizontally,
     ) {
         // --- Top bar: library + settings ------------------------------------
         Row(Modifier.fillMaxWidth(), horizontalArrangement = Arrangement.End) {
+            IconButton(onClick = onOpenQueue) {
+                Icon(Icons.AutoMirrored.Filled.QueueMusic, contentDescription = "Queue")
+            }
             IconButton(onClick = onOpenLibrary) {
                 Icon(Icons.Filled.LibraryMusic, contentDescription = "Albums")
             }
@@ -77,6 +88,16 @@ fun NowPlayingScreen(
             }
         }
 
+        // --- Album art -------------------------------------------------------
+        ArtImage(
+            model = song?.uri?.let { SongArt(it) },
+            iconSize = 96.dp,
+            modifier = Modifier
+                .padding(vertical = 16.dp)
+                .size(240.dp)
+                .clip(RoundedCornerShape(16.dp)),
+        )
+
         // --- Track metadata --------------------------------------------------
         Text(
             text = song?.title ?: song?.uri ?: "Nothing playing",
@@ -171,7 +192,7 @@ fun NowPlayingScreen(
             )
         }
 
-        Spacer(Modifier.weight(1f))
+        Spacer(Modifier.height(24.dp))
 
         TextButton(onClick = vm::disconnect) {
             Text("Disconnect")

app/src/main/kotlin/ca/ksamad/musicremote/ui/PlayerViewModel.kt

@@ -67,7 +67,11 @@ class PlayerViewModel(application: Application) : AndroidViewModel(application)
     fun setVolume(volume: Int) = manager.setVolume(volume)
     fun setRepeat(on: Boolean) = manager.setRepeat(on)
     fun setRandom(on: Boolean) = manager.setRandom(on)
+    fun setConsume(on: Boolean) = manager.setConsume(on)
 
     fun playAlbum(album: String, albumArtist: String?) = manager.playAlbum(album, albumArtist)
     suspend fun loadAlbums() = manager.loadAlbums()
+
+    fun playQueueItem(songId: Int) = manager.playQueueItem(songId)
+    suspend fun loadQueue() = manager.loadQueue()
 }

app/src/main/kotlin/ca/ksamad/musicremote/ui/QueueScreen.kt

@@ -0,0 +1,154 @@
+package ca.ksamad.musicremote.ui
+
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.ArrowBack
+import androidx.compose.material.icons.filled.VolumeUp
+import androidx.compose.material3.CircularProgressIndicator
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.material3.Icon
+import androidx.compose.material3.IconButton
+import androidx.compose.material3.ListItem
+import androidx.compose.material3.ListItemDefaults
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Scaffold
+import androidx.compose.material3.Text
+import androidx.compose.material3.TopAppBar
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.produceState
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.text.style.TextOverflow
+import androidx.compose.ui.unit.dp
+import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import ca.ksamad.musicremote.mpd.model.MpdSong
+import ca.ksamad.musicremote.mpd.model.MpdStatus
+import ca.ksamad.musicremote.playback.SongArt
+
+/**
+ * "Up next": the tracks that will auto-play from the current one to the end of
+ * the queue. We deliberately drop the already-played prefix (MPD keeps played
+ * tracks in the queue unless consume mode is on) so the list reflects what will
+ * actually play before MPD stops — and it shrinks as playback advances even
+ * without consume. Repeat/single change that, so we caption those cases.
+ *
+ * The full queue is re-fetched when its version changes; the upcoming slice is
+ * derived from the live current-song position, so it updates as playback moves.
+ */
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+fun QueueScreen(vm: PlayerViewModel, onBack: () -> Unit) {
+    val status by vm.status.collectAsStateWithLifecycle()
+
+    // Reload the full queue when the queue version bumps (edits/consume).
+    val fullQueue by produceState<List<MpdSong>?>(initialValue = null, status?.playlistVersion) {
+        value = vm.loadQueue()
+    }
+
+    // Slice from the current song to the end. `song` is the current queue index.
+    val currentPos = status?.song
+    val upcoming: List<MpdSong>? = fullQueue?.let { q ->
+        if (currentPos != null && currentPos in q.indices) q.subList(currentPos, q.size) else q
+    }
+    val hasCurrent = currentPos != null && (fullQueue?.indices?.contains(currentPos) == true)
+
+    Scaffold(
+        topBar = {
+            TopAppBar(
+                title = { Text(upcoming?.let { "Up Next (${it.size})" } ?: "Up Next") },
+                navigationIcon = {
+                    IconButton(onClick = onBack) {
+                        Icon(Icons.AutoMirrored.Filled.ArrowBack, contentDescription = "Back")
+                    }
+                },
+            )
+        },
+    ) { innerPadding ->
+        when {
+            upcoming == null -> Box(
+                Modifier.fillMaxSize().padding(innerPadding),
+                contentAlignment = Alignment.Center,
+            ) { CircularProgressIndicator() }
+
+            upcoming.isEmpty() -> Box(
+                Modifier.fillMaxSize().padding(innerPadding),
+                contentAlignment = Alignment.Center,
+            ) { Text("Nothing queued", color = MaterialTheme.colorScheme.onSurfaceVariant) }
+
+            else -> LazyColumn(modifier = Modifier.padding(innerPadding)) {
+                playbackModeCaption(status)?.let { caption ->
+                    item {
+                        Text(
+                            caption,
+                            style = MaterialTheme.typography.bodySmall,
+                            color = MaterialTheme.colorScheme.onSurfaceVariant,
+                            modifier = Modifier
+                                .fillMaxWidth()
+                                .padding(horizontal = 16.dp, vertical = 8.dp),
+                        )
+                    }
+                }
+                items(upcoming, key = { it.id ?: it.uri }) { song ->
+                    // First item is the currently-playing track (when there is one).
+                    val isCurrent = hasCurrent && song === upcoming.first()
+                    ListItem(
+                        modifier = Modifier.clickable { song.id?.let { vm.playQueueItem(it) } },
+                        colors = if (isCurrent) {
+                            ListItemDefaults.colors(containerColor = MaterialTheme.colorScheme.primaryContainer)
+                        } else {
+                            ListItemDefaults.colors()
+                        },
+                        leadingContent = {
+                            ArtImage(
+                                model = SongArt(song.uri),
+                                iconSize = 20.dp,
+                                modifier = Modifier.size(44.dp).clip(RoundedCornerShape(6.dp)),
+                            )
+                        },
+                        headlineContent = {
+                            Text(
+                                song.title ?: song.uri,
+                                maxLines = 1,
+                                overflow = TextOverflow.Ellipsis,
+                                fontWeight = if (isCurrent) FontWeight.Bold else FontWeight.Normal,
+                            )
+                        },
+                        supportingContent = song.artist?.let {
+                            { Text(it, maxLines = 1, overflow = TextOverflow.Ellipsis) }
+                        },
+                        trailingContent = if (isCurrent) {
+                            { Icon(Icons.Filled.VolumeUp, contentDescription = "Now playing") }
+                        } else {
+                            song.duration?.let { { Text(formatDuration(it)) } }
+                        },
+                    )
+                }
+            }
+        }
+    }
+}
+
+/** Explains what will actually happen at the end of the list, given the modes. */
+private fun playbackModeCaption(status: MpdStatus?): String? = when {
+    status == null -> null
+    status.repeat && status.single -> "Repeating the current track."
+    status.single -> "Single mode — stops after the current track."
+    status.repeat -> "Repeat on — the queue loops, so playback won't stop."
+    else -> null
+}
+
+private fun formatDuration(seconds: Double): String {
+    val total = seconds.toInt().coerceAtLeast(0)
+    return "%d:%02d".format(total / 60, total % 60)
+}

app/src/main/kotlin/ca/ksamad/musicremote/ui/SettingsScreen.kt

@@ -1,5 +1,6 @@
 package ca.ksamad.musicremote.ui
 
+import androidx.compose.foundation.clickable
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.fillMaxSize
@@ -18,6 +19,7 @@ import androidx.compose.material3.ListItem
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.OutlinedButton
 import androidx.compose.material3.Scaffold
+import androidx.compose.material3.Switch
 import androidx.compose.material3.Text
 import androidx.compose.material3.TextButton
 import androidx.compose.material3.TopAppBar
@@ -38,6 +40,7 @@ import androidx.lifecycle.compose.collectAsStateWithLifecycle
 @Composable
 fun SettingsScreen(vm: PlayerViewModel, onBack: () -> Unit) {
     val settings by vm.settings.collectAsStateWithLifecycle()
+    val status by vm.status.collectAsStateWithLifecycle()
     var confirmReset by remember { mutableStateOf(false) }
 
     Scaffold(
@@ -73,6 +76,27 @@ fun SettingsScreen(vm: PlayerViewModel, onBack: () -> Unit) {
                 trailingContent = { Text(settings.port.toString()) },
             )
 
+            Text(
+                "Playback",
+                style = MaterialTheme.typography.titleSmall,
+                color = MaterialTheme.colorScheme.primary,
+                modifier = Modifier.padding(start = 8.dp, top = 20.dp, bottom = 4.dp),
+            )
+            // Consume is a live MPD playback option; the switch reflects the
+            // server's current state and toggling sends the `consume` command.
+            val consumeOn = status?.consume == true
+            ListItem(
+                modifier = Modifier.clickable { vm.setConsume(!consumeOn) },
+                headlineContent = { Text("Consume mode") },
+                supportingContent = { Text("Remove each track from the queue after it plays") },
+                trailingContent = {
+                    Switch(
+                        checked = consumeOn,
+                        onCheckedChange = { vm.setConsume(it) },
+                    )
+                },
+            )
+
             Spacer(Modifier.height(24.dp))
 
             OutlinedButton(